α-Hydroxyethylphosphinates, and their use as fungicides

ABSTRACT

A compound of the formula: ##STR1## wherein X is a hydrogen atom, a chlorine atom or a bromine atom and R is an alkyl group, a lower haloalkyl group, a lower cycloalkyl group, a lower alkoxy(lower)alkyl group, a lower alkylthio(lower)alkyl group, a phenoxy(lower)alkyl group, a phenylthio(lower)alkyl group, a phenyl(lower)alkoxy(lower)alkyl group, a phenyl(lower)alkylthio(lower)alkyl group, a lower cycloalkyl(lower)alkyl group, a lower alkyl(lower)cycloalkyl group, a halo(lower)cycloalkyl group, a lower alkylthio(lower)cycloalkyl group, a lower alkoxy(lower)cycloalkyl group, a lower cycloalkyl(lower)cycloalkyl group, a lower alkoxy(lower)alkoxy(lower)alkyl group, a phenyl(lower)alkyl group, a halophenyl(lower)alkyl group, a lower alkylphenyl(lower)alkyl group, a lower alkoxyphenyl(lower)alkyl group, a phenoxyphenyl(lower)alkyl group, a phenylphenyl(lower)alkyl group, a dihalophenyl(lower)alkyl group, a di(lower)alkylphenyl(lower)alkyl group, a di(lower)alkoxyphenyl(lower)alkyl group, a tri(lower)alkoxyphenyl(lower)alkyl group, a naphthyl(lower)alkyl group or an anthracenyl(lower)alkyl group, which is useful as a fungicide.

The present invention relates to α-hydroxyethylphosphinates, and their production and use.

The said α-hydroxyethylphosphinates are representable by the formula: ##STR2## wherein X is a hydrogen atom, a chlorine atom or a bromine atom and R is an alkyl group, a lower haloalkyl group, a lower cycloalkyl group, a lower alkoxy(lower)alkyl group, a lower alkylthio(lower)alkyl group, a phenoxy(lower)alkyl group, a phenylthio(lower)alkyl group, a phenyl(lower)alkoxy(lower)alkyl group, a phenyl(lower)alkylthio(lower)alkyl group, a lower cycloalkyl(lower)alkyl group, a lower alkyl(lower)cycloalkyl group, a halo(lower)cycloalkyl group, a lower alkylthio(lower)cycloalkyl group, a lower alkoxy(lower)cycloalkyl group, a lower cycloalkyl(lower)cycloalkyl group, a lower alkoxy(lower)alkoxy(lower)alkyl group, a phenyl(lower)alkyl group, a halophenyl(lower)alkyl group, a lower alkylphenyl(lower)alkyl group, a lower alkoxyphenyl(lower)alkyl group, a phenoxyphenyl(lower)alkyl group, a phenylphenyl(lower)alkyl group, a dihalophenyl(lower)alkyl group, a di(lower)alkylphenyl(lower)alkyl group, a di(lower)alkoxyphenyl(lower)alkyl group, a tri(lower)alkoxyphenyl(lower)alkyl group, a naphthyl(lower)alkyl group or an anthracenyl(lower)alkyl group.

In the above significances, the number of carbon atoms in the alkyl group is not more than 13. The term "lower" is generally intended to have not more than 8 carbon atoms, and the term "halo" is intended to mean chlorine, bromine, fluorine and iodine, inclusively. Preferred examples of R include C₁ -C₁₀ alkyl, C₂ -C₃ haloalkyl, C₅ -C₆ cycloalkyl, C₁ -C₃ alkoxyethyl, C₁ -C₂ alkylthioethyl, phenoxyethyl, phenylthioethyl, phenylmethoxyethyl, phenylmethylthioethyl, C₃ -C₆ cycloalkylmethyl, methylcyclohexyl, chlorocyclohexyl, methylthiocyclohexyl, methoxycyclohexyl, cyclohexylcyclohexyl, methoxyethoxyethyl, benzyl, halobenzyl, C₁ -C₄ alkylbenzyl, C₁ -C₄ alkoxybenzyl, phenoxybenzyl, phenylbenzyl, dichlorobenzyl, dimethylbenzyl, dimethoxybenzyl, trimethoxybenzyl, phenyl(C₂ -CHD 3)alkyl, chlorophenethyl, methoxyphenethyl, methylphenethyl, naphthyl(C₁ -C₂)alkyl and anthracenylmethyl.

Various fungicides having only a preventive effect have been used for control of plant diseases such as late blight and downy mildew which are caused by infection of Phycomycetes. However, their practical use was limited, since a sufficient controlling effect was hardly produced after the invasion of pathogenic fungi into plant bodies.

It has now been found that the α-hydroxyethylphosphinates (I) show not only a preventive effect but also a curative effect against plant diseases such as late blight and downy mildew caused by infection of Phycomycetes. Thus, they are useful as fungicides.

Examples of phytopathogenic fungi belonging to Phycomycetes, against which the α-hydroxyethylphosphinates (I) can exert their fungicidal activity, are as follows: Peronospora brassicae on vegetables and radish, Peronospora spinaciae on spinach, Peronospora tabacina on tobacco, Pseudoperonospora cubensis on cucumber, Plasmopara viticola on grape, Plasmopara nivea on Umbelliferae plants, Phytophthora cactorum on apple, strawberry and carrot, Phytophthora capsici on tomato and cucumber, Phytophthora cinnamomi on pineapple, Phytophthora infestans on potato, tomato and eggplant, Phytophthora nicotianae var. nicotianae on tobacco, kidney bean and onion, Pythium aphanidermatum on cucumber, Pythium sp. on spinach, Pythium sp. on wheat, Pythium debaryanum on tobacco, Pythium rot (i.e. P. aphanidermatum, P. debaryanum, P. irregulare, P. myriotylum, P. ultimum) on soybean and so forth.

Accordingly, they can be used as fungicides applicable to a plowed field, orchard, tea-garden, mulberry-garden, meadow, lawn and so on.

The α-hydroxyethylphosphinates (I), which may be racemic or optically active, can be produced by various procedures, of which typical examples are as follows:

Procedure (a):

An α-hydroxyethylphosphinic acid of the formula: ##STR3## wherein X is as defined above is reacted with an alcohol of the formula:

    ROH                                                        (III)

wherein R is as defined above to give the α-hydroxyethylphosphinate (I). The reaction is usually carried out by treating the α-hydroxyethylphosphinic acid (II) with the alcohol (III) in an amount of 1.0 to 10 equivalents with respect to the α-hydroxyethylphosphinic acid (II) in a solvent in the presence or absence of a catalyst at a temperature of the boiling point of the solvent for 1 to 24 hours.

Procedure (b):

An α-hydroxyethylphosphinate of the formula: ##STR4## wherein R' is an alkyl group or a cycloalkyl group and X is as defined above is reacted with the alcohol (III) to give the α-hydroxyethylphosphinate (I). The reaction is normally effected by treating the α-hydroxyethylphosphinate (I') with the alcohol (III) in an amount of 1.0 to 10 equivalents with respect to the α-hydroxyethylphosphinate (I') in a solvent in the presence or absence of a catalyst at a temperature of 60° to 150° C. for 1 to 24 hours.

Procedure (c):

The α-hydroxyethylphosphinic acid (II) is reacted with a diazoalkane of the formula:

    R"--N.sub.2                                                (IV)

wherein R" is a methyl group or an ethyl group. The reaction is ordinarily performed by treatment of the α-hydroxyethylphosphinic acid (II) with the diazoalkane (IV) in an amount of 1.0 to 3.0 equivalents with respect to the α-hydroxyethylphosphinic acid (II) in a solvent at a temperature of 0° to 50° C. for 1 to 5 hours.

The produced α-hydroxyethylphosphinates (I) may be subjected to usual work-up or, if necessary, to purification by chromatography, recrystallization or distillation.

In the above procedures, examples of the alcohol (III) are an alkanol (e.g. methanol, ethanol, propanol, isopropanol, butanol, 1-methylpropanol, 2-methylpropanol, pentanol, 1-methylbutanol, 1-ethylpropanol, 3-methylbutanol, 2-methylbutanol, 1,2-dimethylpropanol, hexanol, 1-methylpentanol, heptanol, 1-methylhexanol, 1-ethylpentanol, octanol, 1-methylheptanol, nonanol, decanol, undecanol, dodecanol, tridecanol), a cycloalkanol (e.g. cyclopropanol, 2-methylcyclopropanol, cyclobutanol, 2-methylcyclobutanol, cyclopentanol, 2-methylcyclopentanol, cyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 4-methylcyclohexanol, 4-ethylcyclohexanol), a haloalkanol (e.g. 2-fluoroethanol, 2-chloroethanol, 2-bromoethanol, 3-chloroethanol), an alkoxyalkanol (e.g. 2-methoxyethanol, 2-ethoxyethanol, 2-isopropoxyethanol, 3-methoxypropanol), an alkoxyalkoxyalkanol (e.g. 2-(2-methoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol), an alkylthioalkanol (e.g. 2-methylthioethanol, 2-ethylthioethanol, 2-isopropylthioethanol), an aralkyloxyalkanol (e.g. 2-benzyloxyethanol, 2-(2-phenylethoxy)ethanol, 2-(4-chlorobenzyloxy)ethanol, 2-(1-naphthylmethoxy)ethanol), a cycloalkylalkanol (e.g. cyclohexylmethanol, 2-cyclohexylethanol), an aralkylthioalkanol (e.g. 2-benzylthioethanol, 2-(4-methylbenzylthio)ethanol), an aryloxyalkanol (e.g. 2-phenoxyethanol, 3-phenoxypropanol, 2-(4-chclophenoxy)ethanol), an arylthioalkanol (e.g. 2-phenylthioethanol, 4-phenylthiobutanol, 2-(1-naphthylthio)ethanol), a halocycloalkanol (e.g. 2-chlorocyclohexanol, 4-bromocyclohexanol), an alkoxycycloalkanol (e.g. 2-methoxycyclohexanol, 4-methoxycyclohexanol), an alkylthiocycloalkanol (e.g. 4-methylthiocyclohexanol, 4-ethylthiocyclohexanol), a cycloalkylcycloalkanol (e.g. 4-cyclohexylcyclohexanol, 2-cyclopentylcyclopentanol), a benzyl alcohol (e.g. benzyl alcohol, 2-fluorobenzyl alcohol, 3-fluorobenzyl alcohol, 4-fluorobenzyl alcohol, 2-chlorobenzyl alcohol, 3-chlorobenzyl alcohol, 4-chlorobenzyl alcohol, 2-bromobenzyl alcohol, 3-bromobenzyl alcohol, 4-bromobenzyl alcohol, 2-iodobenzyl alcohol, 3-iodobenzyl alcohol, 4-iodobenzyl alcohol, 2-methylbenzyl alcohol, 3-methylbenzyl alcohol, 4- methylbenzyl alcohol, 2-ethylbenzyl alcohol, 3 -ethylbenzyl alcohol, 4-ethylbenzyl alcohol, 4-isopropylbenzyl alcohol, 4-t-butylbenzyl alcohol, 2-methoxybenzyl alcohol, 3-methoxybenzyl alcohol, 4-methoxybenzyl alcohol, 2-ethoxybenzyl alcohol, 3-ethoxybenzyl alcohol, 4-ethoxybenzyl alcohol, 2-propoxybenzyl alcohol, 3-propoxybenzyl alcohol, 4-propoxybenzyl alcohol, 2-isopropoxybenzyl alcohol, 3-isopropoxybenzyl alcohol, 4-isopropoxybenzyl alcohol, 4-butoxybenzyl alcohol, 3-phenoxybenzyl alcohol, 4-phenoxybenzyl alcohol, 4-phenylbenzyl alcohol, 2,4-dichlorobenzyl alcohol, 2,3-dichlorobenzyl alcohol, 2,5-dichlorobenzyl alcohol, 2,6-dichlorobenzyl alcohol, 3,4-dichlorobenzyl alcohol, 3,5-dichlorobenzyl alcohol, 3-trifluoromethylbenzyl alcohol, 2-fluoro-6-chlorobenzyl alcohol, 2,3-dimethoxybenzyl alcohol, 2,4-dimethoxybenzyl alcohol, 2,5-dimethoxybenzyl alcohol, 3,4-dimethoxybenzyl alcohol, 3,5-dimethoxybenzyl alcohol, 2,3,4-trimethoxybenzyl alcohol, 2,4,5-trimethoxybenzyl alcohol, 3,4,5-trimethoxybenzyl alcohol, 2,4,6-trimethoxybenzyl alcohol), a phenethyl alcohol (e.g. 1-phenylethanol, 2-phenylethanol, 1-(4-chlorophenyl)ethanol, 1-(2-fluorophenyl)ethanol, 1-(3-bromophenyl)ethanol, 1-(3,4-dichlorophenyl)ethanol, 1-(4-methylphenyl)ethanol, 1-(4-methoxyphenyl)ethanol, 1-(3-trifluoromethylphenyl)ethanol, 1-(2-chloro-4-bromophenyl)ethanol, 1-(3,4,5-trimethoxyphenyl)ethanol, 2-(4-methylphenyl)ethanol, 2-(4-chlorophenylethanol, 2-(2-methoxyphenyl)ethanol, 2-(4-methoxyphenyl)ethanol, 2-(2,4-dichlorophenyl)ethanol), a phenylpropyl alcohol (e.g. 1-phenylpropanol, 2-phenylpropanol, 3-phenylpropanol), a naphthyl alcohol (e.g. 1-naphthylmethanol, 2-naphthylmethanol, 2-(1-naphthylethanol), an anthracenyl alcohol (e.g., 9-antracenyl alcohol), etc. Any of these alcohols can simultaneously play a role of the solvent for the reaction medium.

Preferred examples of the solvent in the procedure (a) or (b) are aromatic hydrocarbons (e.g. benzene, toluene, xylene), halogenated hydrocarbons (e.g. chlorobenzene), aliphatic hydrocarbons (e.g. hexane, heptane, ligroin), etc. Favorable examples of the solvent in the procedure (c) are ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, etc. They may be employed alone or in combination.

Examples of the catalyst which may be used in the procedure (a) or (b) are mineral acids (e.g. hydrochloric acid, sulfuric acid).

The starting racemic α-hydroxyethylphosphinic acid (II) can be produced according to the method disclosed in Annales. de Chimie et de Physique., 23, 289-362 (1891). They can be also produced by reacting an acetal of the formula:

    XCH.sub.2 CH(OR').sub.2                                    (V)

wherein X and R' are each as defined above with aqueous phosphinic acid in the presence of an acid catalyst (e.g. hydrochloric acid, sulfuric acid), usually at a temperature of 10° to 100° C. for 5 to 24 hours. The amount of the phosphinic acid may be 1.0 to 10 equivalents with respect to the acetal (V).

Some typical examples of the production of the α-hydroxyethylphosphinic acid (II) are shown in the following Reference Examples.

REFERENCE EXAMPLE 1

A solution of chloroacetaldehyde dimethylacetal (124.5 g) and phosphinic acid (50%, 132 g) was heated at 50° to 60° C. for 26 hours in the presence of conc. hydrochloric acid (10 ml). The resultant mixture was concentrated in vacuo to give 140 g (96.7%) of α-hydroxy-β-chloroethylphosphinic acid. n_(D) ²².0 1.4970.

REFERENCE EXAMPLE 2

A solution of bromoacetaldehyde diethylacetal (197 g) and phosphinic acid (50%, 132.0 g) was heated at 60° to 70° C. for 48 hours in the presence of sulfuric acid (0.5 g). The resultant mixture was concentrated in vacuo to give 187.0 g (98.9%) of α-hydroxy-β-bromoethylphosphinic acid. n_(D) ²³ 1.5105.

The optically active α-hydroxyethylphosphinates (I) can be produced by using an optically active α-hydroxyethylphosphinic acid (II) in the above mentioned procedures.

Practical and presently preferred embodiments for production of the α-hydroxyethylphosphinates (I) are shown in the following Examples.

EXAMPLE 1

A solution of α-hydroxyethylphosphinic acid (2.2 g) and 1-butanol (5.0 g) in benzene (30 ml) was heated for 3 hours with removal of water through a Dean-Stark apparatus. After cooling, the reaction mixture was washed with water, dried over magnesium sulfate and concentrated in vacuo to give 2.71 g (81.6%) of n-butyl α-hydroxyethylphosphinate (Compound No. 5).

EXAMPLE 2

A 10% solution of diazomethane in ether was gradually added to a stirred and ice-cooled solution of α-hydroxyethylphosphinic acid (3.0 g) in tetrahydrofuran (10 ml) until the color of the solution turned to yellow. After 10 minutes, the solvent was evaporated in vacuo. The residue was distilled to give 2.28 g (67.3%) of methyl α-hydroxyethylphosphinate (Compound No. 1).

EXAMPLE 3

A solution of Compound No. 1 (1.03 g) in ethanol (5 g) was heated under reflux for 5 hours. The solvent was evaporated in vacuo, and the residue was distilled to give 430 mg (38.47%) of ethyl α-hydroxyethylphosphinate (Compound No. 2).

EXAMPLE 4

In the same manner as in Example 2 but using (+)-α-hydroxyethylphosphinic acid (400 mg; [α]_(D) =+15.2° (H₂ O)), there was prepared 188 mg of methyl (+)-α-hydroxyethylphosphinate ([α]_(D) =+6.7° (CHCl₃)).

EXAMPLE 5

In the same manner as in Example 2 but using (-)-α-hydroxyethylphosphinic acid (340 mg; [α]_(D) =-15.5° (H₂ O)), there was prepared 184 mg of methyl (-)-α-hydroxyethylphosphinate ([α]_(D) =-7.1° (CHCl₃)).

EXAMPLE 6

A solution of α-hydroxyethylphosphinic acid (5.5 g) and benzyl alcohol (2.26 g) in benzene (50 ml) was heated for 8 hours with removal of water through a Dean-Stark apparatus. After cooling, the reaction mixture was washed with water, dried over magnesium sulfate and concentrated in vacuo to give 3.65 g (91.2%) of benzyl α-hydroxyethylphosphinate (Compound No. 36).

EXAMPLE 7

A solution of α-hydroxyethylphosphinic acid (5.5 g) and 4-chloro-α-phenethyl alcohol (1.56 g) in benzene (50 ml) was heated for 10 hours with removal of water through a Dean-Stark apparatus. The same work-up as in Example 6 gave 2.38 g (95.7%) of 4-chloro-α'-phenethyl α-hydroxyethylphosphinate (Compound No. 68).

EXAMPLE 8

A solution of α-hydroxy-β-chloroethylphosphinic acid (2.9 g) and 1-butanol (10.0 g) in benzene (30 ml) was heated for 3 hours with removal of water through a Dean-Stark apparatus. The same work-up as in Example 6 gave 2.60 g (64.8%) of n-butyl α-hydroxy-β-chloroethylphosphinate (Compound No. 82).

EXAMPLE 9

A solution of α-hydroxy-β-bromoethylphosphinic acid (1.9 g) in tetrahydrofuran (10.0 g) was treated with diazomethane in ether until the color of the solution turned to yellow. The same work-up as in Example 2 gave 1.70 g (83.7%) of methyl α-hydroxy-β-bromoethylphosphinate (Compound No. 88).

Some examples of the α-hydroxyethylphosphinates (I) produced as above are shown in Table 1.

                  TABLE 1                                                          ______________________________________                                         Compound                                                                       No.     X     R                Physical constant                               ______________________________________                                         1       H     CH.sub.3         n.sub.D.sup.24 1.4563 (98-                                                     100° C./0.15 mmHg)                       2       H     C.sub.2 H.sub.5  n.sub.D.sup.20 1.4552 (93-                                                     96° C./0.06 mmHg)                        3       H     n-C.sub.3 H.sub.7                                                                               n.sub.D.sup.20.0 1.4535                         4       H     i-C.sub.3 H.sub.7                                                                               n.sub.D.sup.25 1.4502                           5       H     n-C.sub.4 H.sub.9                                                                               n.sub.D.sup.22 1.4485                           6       H     i-C.sub.4 H.sub.9                                                                               n.sub.D.sup.19 1.4462                           7       H     n-C.sub.5 H.sub.11                                                                              n.sub.D.sup.20 1.4505                           8       H     i-C.sub.5 H.sub.11                                                                              n.sub.D.sup.21 1.4505                           9       H     n-C.sub.6 H.sub.13                                                                              n.sub.D.sup.20 1.4515                           10      H     n-C.sub.7 H.sub.15                                                                              n.sub.D.sup.20.0 1.4503                         11      H     n-C.sub.8 H.sub.17                                                                              n.sub.D.sup.20.0 1.4572                         12      H     n-C.sub.10 H.sub.21                                                                             n.sub.D.sup.19.0 1.4561                         13      H     FCH.sub.2 CH.sub.2                                                                              n.sub.D.sup.25.0 1.4528                         14      H     ClCH.sub.2 CH.sub.2                                                                             n.sub.D.sup.18.0 1.4743                         15      H     ClCH.sub.2 CH.sub.2 CH.sub.2                                                                    n.sub. D.sup.21.0 1.4650                        16      H                                                                                     ##STR5##        n.sub.D.sup.20 1.4730                           17      H                                                                                     ##STR6##        n.sub.D.sup.20.0 1.4752                         18      H     CH.sub.3 OCH.sub.2 CH.sub.2                                                                     n.sub.D.sup.20.0 1.4428                         19      H     C.sub.2 H.sub.5 OCH.sub.2 CH.sub.2                                                              n.sub.D.sup.20.0 1.4435                         20      H     i-C.sub.3 H.sub.7 OCH.sub.2 CH.sub.2                                                            n.sub.D.sup.18.0 1.4480                         21      H     CH.sub.3 SCH.sub.2 CH.sub.2                                                                     n.sub.D.sup.20.0 1.4980                         22      H     C.sub.2 H.sub.5 SCH.sub.2 CH.sub.2                                                              n.sub.D.sup.20.0 1.4885                         23      H                                                                                     ##STR7##        n.sub.D.sup.20.0 1.5665                         24      H                                                                                     ##STR8##        n.sub.D.sup.20.0 1.5188                         25      H                                                                                     ##STR9##        n.sub.D.sup.20.0 1.5260                         26      H                                                                                     ##STR10##       n.sub.D.sup.20.0 1.5630                         27      H                                                                                     ##STR11##       n.sub.D.sup.20.0 1.4460                         28      H                                                                                     ##STR12##       n.sub.D.sup.20.0 1.4722                         29      H                                                                                     ##STR13##       n.sub.D.sup.20 1.4690                           30      H     sec-C.sub.4 H.sub.9                                                                             n.sub.D.sup.20 1.4460                           31      H                                                                                     ##STR14##       n.sub.D.sup.21 1.5633                           32      H                                                                                     ##STR15##       n.sub.D.sup.20 1.5565                           33      H                                                                                     ##STR16##       n.sub.D.sup.20 1.5230                           34      H                                                                                     ##STR17##       n.sub.D.sup.20 1.5650                           35      H     CH.sub.3 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2                                                  n.sub.D.sup.20 1.4900                           36      H                                                                                     ##STR18##       n.sub.D.sup.20.0 1.5325                         37      H                                                                                     ##STR19##       n.sub.D.sup.20.0 1.5112                         38      H                                                                                     ##STR20##       n.sub.D.sup.19.5 1.5085                         39      H                                                                                     ##STR21##       n.sub.D.sup.20.0 1.5100                         40      H                                                                                     ##STR22##       n.sub.D.sup.20.0 1.5490                         41      H                                                                                     ##STR23##       n.sub.D.sup.19.5 1.5500                         42      H                                                                                     ##STR24##       n.sub.D.sup.21.0 1.5453                         43      H                                                                                     ##STR25##       n.sub.D.sup.20.0 1.5638                         44      H                                                                                     ##STR26##       n.sub.D.sup.19.5 1.5651                         45      H                                                                                     ##STR27##       M.P. 58-61° C.                           46      H                                                                                     ##STR28##       n.sub.D.sup.20.0 1.5720                         47      H                                                                                     ##STR29##       n.sub.D.sup.20.0 1.5261                         48      H                                                                                     ##STR30##       n.sub.D.sup.20.0 1.5290                         49      H                                                                                     ##STR31##       n.sub.D.sup.19.5 1.5286                         50      H                                                                                     ##STR32##       n.sub.D.sup.20.5 1.5310                         51      H                                                                                     ##STR33##       n.sub.D.sup.19.5 1.5102                         52      H                                                                                     ##STR34##       n.sub.D.sup.20.0 1.5150                         53      H                                                                                     ##STR35##       n.sub.D.sup.19.5 1.5320                         54      H                                                                                     ##STR36##       n.sub.D.sup.19.5 1.5335                         55      H                                                                                     ##STR37##       n.sub.D.sup.20.5 1.5390                         56      H                                                                                     ##STR38##       n.sub.D.sup.20.0 1.5432                         57      H                                                                                     ##STR39##       n.sub.D.sup.20.5 1.5436                         58      H                                                                                     ##STR40##       n.sub.D.sup.20.0 1.5420                         59      H                                                                                     ##STR41##       n.sub.D.sup.20.0 1.5488                         60      H                                                                                     ##STR42##       Waxy material                                   61      H                                                                                     ##STR43##       n.sub.D.sup.19.0 1.5632                         62      H                                                                                     ##STR44##       n.sub.D.sup.20.0 1.5537                         63      H                                                                                     ##STR45##       n.sub.D.sup.19.5 1.5258                         64      H                                                                                     ##STR46##       n.sub.D.sup.20.0 1.5236                         65      H                                                                                     ##STR47##       n.sub.D.sup.20.0 1.5350                         66      H                                                                                     ##STR48##       n.sub.D.sup.20.0 1.5256                         67      H                                                                                     ##STR49##       n.sub.D.sup.19.5 1.5225                         68      H                                                                                     ##STR50##       n.sub.D.sup.20.0 1.5460                         69      H                                                                                     ##STR51##       n.sub.D.sup.17.0 1.5278                         70      H                                                                                     ##STR52##       n.sub.D.sup.19.5 1.5210                         71      H                                                                                     ##STR53##       n.sub.D.sup.20.0 1.5390                         72      H                                                                                     ##STR54##       n.sub.D.sup.20.0 1.5286                         73      H                                                                                     ##STR55##       n.sub.D.sup.21.0 1.5248                         74      H                                                                                     ##STR56##       n.sub.D.sup. 19.0 1.5185                        75      H                                                                                     ##STR57##       n.sub.D.sup.19.5 1.5220                         76      H                                                                                     ##STR58##       n.sub.D.sup.20.0 1.5705                         77      H                                                                                     ##STR59##       n.sub.D.sup.20.0 1.5653                         78      H                                                                                     ##STR60##       n.sub.D.sup.20.0 1.5750                         79      Cl    CH.sub.3         n.sub.D.sup.25 1.4562                           80      Cl    C.sub.2 H.sub.5  n.sub.D.sup.25 1.4555                           81      Cl    n-C.sub.3 H.sub.7                                                                               n.sub.D.sup.25 1.4530                           82      Cl    n-C.sub.4 H.sub.9                                                                               n.sub.D.sup.23 1.4560                           83      Cl    i-C.sub.4 H.sub.9                                                                               n.sub.D.sup.27 1.4458                           84      Cl    sec-C.sub.4 H.sub.9                                                                             n.sub.D.sup.27 1.4482                           85      Cl    n-C.sub.5 H.sub.11                                                                              n.sub.D.sup.27 1.4465                           86      Cl    i-C.sub.5 H.sub.11                                                                              n.sub.D.sup.27 1.4430                           87      Cl    n-C.sub.6 H.sub.13                                                                              n.sub.D.sup.27 1.4425                           88      Br    CH.sub.3         n.sub.D.sup.25 1.5050                           89      Br    C.sub.2 H.sub.5  n.sub.D.sup. 25 1.5005                          90      Br    n-C.sub.3 H.sub.7                                                                               n.sub.D.sup.25.0 1.4905                         91      Br    i-C.sub.3 H.sub.7                                                                               n.sub.D.sup.25.0 1.4865                         92      Br    n-C.sub.4 H.sub.9                                                                               n.sub.D.sup.25 1.4935                           93      Br    i-C.sub.4 H.sub.9                                                                               n.sub.D.sup.25.0 1.4890                         94      Br    sec-C.sub.4 H.sub.9                                                                             n.sub.D.sup.25 1.4860                           95      Br    n-C.sub.5 H.sub.11                                                                              n.sub.D.sup.25 1.4749                           96      Cl                                                                                    ##STR61##       n.sub.D.sup.25 1.4912                           97      Br                                                                                    ##STR62##       n.sub.D.sup.25 1.4960                           98      Cl    ClCH.sub.2 CH.sub.2                                                                             n.sub.D.sup.25 1.5095                           99      Br    ClCH.sub.2 CH.sub.2                                                                             n.sub.D.sup.25 1.5100                           100     Cl    FCH.sub.2 CH.sub.2                                                                              n.sub.D.sup.25 1.5001                           101     Cl    CH.sub.3 OCH.sub.2 CH.sub.2                                                                     n.sub.D.sup.25 1.4950                           102     Cl    C.sub.2 H.sub.5 OCH.sub.2 CH.sub.2                                                              n.sub.D.sup.25 1.4865                           103     Br    CH.sub.3 OCH.sub.2 CH.sub.2                                                                     n.sub.D.sup.25 1.5115                           104     Br    i-C.sub.3 H.sub.7 OCH.sub.2 CH.sub.2                                                            n.sub.D.sup.25 1.5105                           105     Br    i-C.sub.5 H.sub.11                                                                              n.sub.D.sup.25 1.4723                           ______________________________________                                    

In actual application as fungicides, the α-hydroxyethylphosphinates (I) may be used alone without incorporation of other ingredients. For easier application, however, they are normally employed in admixture with solid or liquid carriers or diluents. The fungicidal compositions can be formulated into any of the ordinarily adopted forms such as, for example, dusts, granules, wettable powders, emulsifiable concentrates, fine particles, aqueous solutions, oil sprays, aerosols and tablets. Such compositions generally contain 0.1 to 99.9% by weight, preferably 2.0 to 80.0% by weight, of the active ingredient.

As the solid carriers or diluents usable for formulation of the fungicidal composition, there may be exemplified plant carriers (e.g. wheat flour, tobacco powder, soybean powder, walnut-shell powder, wooden powder, saw dust, wheat bran, bark dust, cellulose powder, extract residue), fibrous products (e.g. paper, cardboard, rag), crushed synthetic resins, clays (e.g. kaolin, bentonite, terra alba), talcs, other inorganic minerals (e.g. pyrophyllite, celicite, pumice, sulfur powder, diatomaceous earth, white carbon, activated carbon), chemical fertilizers (e.g. ammonium sulfate, ammonium phosphate, ammonium nitrate, urea, ammonium chloride), etc. As the liquid carriers or diluents, there may be employed water, alcohols (e.g. methanol, ethanol), ketones (e.g. acetone, methylethylketone), ethers (e.g. diethyl ether, dioxane, cellosolve, tetrahydrofuran), aromatic hydrocarbons (e.g. benzene, toluene, xylene, methylnaphthalene), aliphatic hydrocarbons (e.g. gasoline, kerosene, lamp oil), esters, nitriles, acid amides (e.g. methylformamide, dimethylacetamide), halogenated hydrocarbons (e.g. dichloroethane, trichloroethylene, carbon tetrachloride), etc.

In addition to the solid or liquid carriers or diluents as exemplified above, there may be used surfactants when desired. Examples of the surfactants are polyoxyethylene phenylphenol polymer, polyoxyethylene alkylaryl ether, sodium laurylsulfate, calcium alkylbenzenesulfonate, alkylsulfates, alkylsulfonates, alkylarylsulfonates, polyethyleneglycol ethers, polyvalent alcohol esters, etc. There may be also used adhesive agents, dispersing agents, stabilizers, etc. Specific examples thereof include casein, gelatin, starch, carboxymethyl cellulose, gum arabic, alginate, calcium ligninsulfonate, bentonite, molasses, polyvinyl alcohol, palm oil, agar, acid isopropyl phosphate, tricresyl phosphate, tall oil, epoxylated oil, surfactants, aliphatic acids and their esters, etc.

Moreover, the fungicidal composition may comprise other fungicides, insecticides, nematocides, acaricides, insect repellents, plant growth regulators, herbicides, fertilizers, soil improvers, etc.

Some typical examples of the fungicidal composition of this invention are shown below. In those examples, part(s) and % are by weight unless otherwise indicated.

EXAMPLE A

Compound No. 37 (2 parts), clay (88 parts) and talc (10 parts) were thoroughly pulverized and mixed together to obtain a dust containing 2% of the active ingredient.

EXAMPLE B

Compound No. 6 (30 parts), diatomaceous earth (45 parts), white carbon (20 parts), a wetting agent (sodium laurylsulfate) (3 parts) and a dispersing agent (calcium ligninsulfonate) (2 parts) were thoroughly pulverized and mixed together to obtain a wettable powder containing 30% of the active ingredient.

EXAMPLE C

Compound No. 45 (50 parts), diatomaceous earth (45 parts), a wetting agent (calcium alkylbenzenesulfonate) (2.5 parts) and a dispersing agent (calcium ligninsulfonate) (2.5 parts) were thoroughly pulverized and mixed together to obtain a wettable powder containing 50% of the active ingredient.

EXAMPLE D

Compound No. 18 (20 parts), xylene (60 parts) and an emulsifier (polyoxyethylene phenylphenol polymer type) (20 parts) were mixed together to obtain an emulsifiable concentrate containing 20% of the active ingredient.

EXAMPLE E

Compound No. 1 (50 parts), water (45 parts) and a wetting agent (polyoxyethylene alkylaryl ether type) (5 parts) were mixed together to obtain an aqueous solution containing 50% of the active ingredient.

A suitable amount of the fungicidal composition of the invention to be applied is generally from 10 to 1000 grams in terms of the active ingredient per 10 are. In case of the composition form such as a wettable powder, emulsifiable concentrate or aqueous solution, it is normally diluted with water and then applied. The concentration of the active ingredient upon application is preferably within the range of 0.01 to 1% by weight. In case of the composition form such as dust or granules, it is ordinarily applied as such. Since, however, the amount and concentration largely depend upon the composition forms, application times, application methods, application sites, diseases and crops, they may be increased or decreased appropriately.

The following examples show some typical test results supporting the excellent fungicidal activity of the α-hydroxyethylphosphinates (I). In these examples, the compound numbers correspond to those in Table 1. The compounds used for comparison are as follows:

    ______________________________________                                         Compound                                                                       No.     Structure          Remarks                                             ______________________________________                                                  ##STR63##         Commercially avail- able fungicide "chlorothalo                                nil"                                                B                                                                                       ##STR64##         Commercially available fungi- cide "alliete"        C                                                                                       ##STR65##         Commercially avail- able fungicide "zineb"          D                                                                                       ##STR66##         Commercially avail- able fungicide "maneb"          ______________________________________                                    

EXAMPLE I

Seeds of cucumber (species: "Sagamihanjiro") were sowed in soil filled in plastic pots and cultivated in a greenhouse for 14 days to obtain seedlings of cucumber having cotyledons. An aqueous dilution of the test compound in the form of an emulsifiable concentrate or wettable powder was applied onto the seedlings by foliar treatment. Then, the seedlings were grown in the greenhouse for 5 days. A spore suspension of Pseudoperonospora cubensis was sprayed onto the seedlings, which were placed at 20° C. under a humid condition for 3 days and then grown at 20° C. under the irradiation with a fluorescent lamp for 3 days. The state of infection of the test plants was observed, and the preventive value was calculated according to the following equation:

    ______________________________________                                         Infection index State of infection                                             ______________________________________                                         0               No infectious spot on leaf                                     0.5             Infectious spots of less than                                                  5% of the area of leaf                                         1               Infectious spots of less than                                                  20% of the area of leaf                                        2               Infectious spots of less than                                                  50% of the area of leaf                                        4               Infectious spots of not less                                                   than 50% of the area of leaf                                   ______________________________________                                          ##STR67##                                                                      ##STR68##                                                                

The results are shown in Table 2.

                  TABLE 2                                                          ______________________________________                                         Compound    Concentration of                                                                               Preventive                                         No.         active ingredient (ppm)                                                                        value (%)                                          ______________________________________                                          1          200             100                                                 2          200             100                                                 3          200             100                                                 4          200             100                                                 5          200             100                                                 6          200             100                                                 7          200             100                                                 8          200             100                                                 9          200              95                                                10          200              90                                                11          200              75                                                12          200             100                                                13          200             100                                                14          200             100                                                15          200             100                                                16          200             100                                                17          200             100                                                18          200             100                                                19          200             100                                                20          200             100                                                21          200             100                                                22          200             100                                                23          200             100                                                24          200             100                                                25          200             100                                                26          200             100                                                27          200             100                                                28          200             100                                                29          200             100                                                30          200             100                                                36          200             100                                                37          200             100                                                40          200             100                                                47          200             100                                                48          200             100                                                50          200             100                                                53          200             100                                                55          200             100                                                58          200              95                                                64          200              90                                                66          200             100                                                69          200             100                                                74          200             100                                                75          200             100                                                76          200              85                                                80          200             100                                                82          200              95                                                84          200             100                                                88          200             100                                                89          200             100                                                91          200             100                                                94          200              93                                                97          200              91                                                100         200             100                                                105         200             100                                                B           200              44                                                ______________________________________                                    

EXAMPLE II

Seeds of cucumber (species: "Sagamihanjiro") were sowed in soil filled in plastic pots and cultivated in a greenhouse for 14 days to obtain seedlings of cucumber having cotyledons. The seedlings were treated by soil-drench with an aqueous dilution of the test compound in the form of an emulsifiable concentrate or wettable powder. After 4 days, a spore suspension of Pseudoperonospora cubensis was sprayed onto the seedlings, which were placed at 20° C. under a humid condition for 3 days and then grown at 20° C. under irradiation with a fluorescent lamp for 4 days. The state of infection of the plants was observed, and the preventive value was calculated as in Example I.

The results are shown in Table 3.

                  TABLE 3                                                          ______________________________________                                         Compound     Amount of active                                                                            Preventive                                           No.          ingredient (g/are)                                                                          value (%)                                            ______________________________________                                          1           100          100                                                   2           100          100                                                   3           100          100                                                   4           100          100                                                   5           100          100                                                   6           100          100                                                   7           100          100                                                  10           100          100                                                  13           100          100                                                  14           100          100                                                  16           100          100                                                  18           100          100                                                  19           100          100                                                  21           100          100                                                  36           100          100                                                  37           100          100                                                  38           100          100                                                  39           100          100                                                  40           100          100                                                  41           100          100                                                  42           100          100                                                  43           100          100                                                  44           100          100                                                  45           100          100                                                  46           100          100                                                  47           100          100                                                  48           100          100                                                  49           100          100                                                  50           100          100                                                  51           100          100                                                  52           100          100                                                  53           100          100                                                  54           100          100                                                  55           100          100                                                  56           100          100                                                  57           100          100                                                  58           100          100                                                  59           100          100                                                  60           100          100                                                  61           100          100                                                  62           100          100                                                  63           100          100                                                  64           100          100                                                  65           100          100                                                  66           100          100                                                  67           100          100                                                  68           100          100                                                  69           100          100                                                  70           100          100                                                  71           100          100                                                  72           100          100                                                  73           100          100                                                  74           100          100                                                  75           100          100                                                  76           100          100                                                  77           100          100                                                  78           100          100                                                  79           100          100                                                  80           100          100                                                  81           100          100                                                  82           100          100                                                  83           100          100                                                  84           100          100                                                  85           100          100                                                  86           100          100                                                  87           100          100                                                  88           100          100                                                  89           100          100                                                  90           100          100                                                  91           100          100                                                  92           100          100                                                  93           100          100                                                  94           100          100                                                  95           100          100                                                  96           100          100                                                  97           100          100                                                  98           100          100                                                  99           100          100                                                  100          100          100                                                  101          100          100                                                  102          100          100                                                  103          100          100                                                  104          100          100                                                  105          100          100                                                  A            100           0                                                   B            100           25                                                  ______________________________________                                    

EXAMPLE III

Seeds of grape (species: "Delaware") were sowed in soil filled in plastic pots and cultivated in a greenhouse for 1 month to obtain seedlings of grape at the 2 to 3-leaved stage. A spore suspension of Plasmopara viticola was sprayed onto the seedlings, which were placed at 23° C. under a humid condition for 2 days. Then, an aqueous dilution of the test compound in the form of an emulsifiable concentrate or wettable powder was applied onto the seedlings by foliar treatment. Thereafter, the seedlings were grown at 23° C. under irradiation with a fluorescent lamp for 14 days. The state of infection of the plants was observed, and the preventive value was calculated as in Example I.

The results are shown in Table 4.

                  TABLE 4                                                          ______________________________________                                         Compound    Concentration of                                                                               Preventive                                         No.         active ingredient (ppm)                                                                        value (%)                                          ______________________________________                                          1          500             100                                                 2          500             100                                                 3          500             100                                                 4          500             100                                                13          500             100                                                14          500             100                                                16          500             100                                                18          500             100                                                36          500             100                                                37          500             100                                                39          500             100                                                40          500             100                                                43          500             100                                                47          500             100                                                50          500             100                                                53          500             100                                                54          500             100                                                61          500             100                                                66          500             100                                                68          500             100                                                74          500             100                                                76          500             100                                                79          500             100                                                80          500             100                                                88          500             100                                                89          500             100                                                91          500             100                                                96          500             100                                                100         500             100                                                B           500              69                                                C           1000             0                                                 ______________________________________                                    

EXAMPLE IV

Seeds of potato (species: "Danshaku") were sowed in soil filled in plastic pots and cultivated in a greenhouse for 2 months to obtain seedlings of potato. A spore suspension of Phytophthora infestans was sprayed onto the seedlings, which were placed at 20° C. under a humid condition for 20 hours. Then, an aqueous dilution of the test compound in the form of an emulsifiable concentrate or wettable powder was applied onto the seedlings by foliar treatment. Thereafter, the seedlings were grown at 20° C. under a humid condition for 6 days. The state of infection of the plants was observed, and the preventive value was calculated as in Example I.

The results are shown in Table 5.

                  TABLE 5                                                          ______________________________________                                         Compound    Concentration of                                                                               Preventive                                         No.         active ingredient (ppm)                                                                        value (%)                                          ______________________________________                                          1          500             95                                                  2          500             90                                                  3          500             90                                                  5          500             93                                                  8          500             91                                                 13          500             95                                                 14          500             97                                                 16          500             92                                                 18          500             95                                                 21          500             90                                                 36          500             90                                                 38          500             95                                                 42          500             85                                                 43          500             91                                                 54          500             93                                                 66          500             87                                                 71          500             90                                                 74          500             91                                                 80          500             87                                                 88          500             83                                                 89          500             90                                                 95          500             93                                                 99          500             95                                                 D           1000             0                                                 ______________________________________                                     

What is claimed is:
 1. A compound of the formula: ##STR69## wherein X is a hydrogen atom, a chlorine atom or a bromine atom and R is an alkyl group, a lower haloalkyl group, a lower cycloalkyl group, a lower alkoxy(lower)alkyl group, a lower alkylthio(lower)alkyl group, a phenoxy(lower)alkyl group, a phenylthio(lower)alkyl group, a phenyl(lower)alkoxy(lower)alkyl group, a phenyl(lower)alkylthio(lower)alkyl group, a lower cycloalkyl(lower)alkyl group, a lower alkyl(lower)cycloalkyl group, a halo(lower)cycloalkyl group, a lower alkylthio(lower)cycloalkyl group, a lower alkoxy(lower)cycloalkyl group, a lower cycloalkyl(lower)cycloalkyl group, a lower alkoxy(lower)alkoxy(lower)alkyl group, a phenyl(lower)alkyl group, a halophenyl(lower)alkyl group, a lower alkylphenyl(lower)alkyl group, a lower alkoxyphenyl(lower)alkyl group, a phenoxyphenyl(lower)alkyl group, a phenylphenyl(lower)alkyl group, a dihalophenyl(lower)alkyl group, a di(lower)alkylphenyl(lower)alkyl group, a di(lower)alkoxyphenyl(lower)alkyl group, a tri(lower)alkoxyphenyl(lower)alkyl group, a naphthyl(lower)alkyl group or an anthracenyl(lower)alkyl group.
 2. The compound according to claim 1, wherein X is hydrogen, chlorine or bromine and R is C₁ -C₁₀ alkyl, C₂ -C₃ haloalkyl, C₅ -C₆ cycloalkyl, C₁ -C₃ alkoxyethyl, C₁ -C₂ alkylthioethyl, phenoxyethyl, phenylthioethyl, phenylmethoxyethyl, phenylmethylthioethyl, C₃ -C₆ cycloalkylmethyl, methylcyclohexyl, chlorocyclohexyl, methylthiocyclohexyl, methoxycyclohexyl, cyclohexylcyclohexyl, methoxyethoxyethyl, benzyl, halobenzyl, C₁ -C₄ alkylbenzyl, C₁ -C₄ alkoxybenzyl, phenoxybenzyl, phenylbenzyl, dichlorobenzyl, dimethylbenzyl, dimethoxybenzyl, trimethoxybenzyl, phenyl(C₂ -C₃)alkyl, chlorophenethyl, methoxyphenethyl, methylphenethyl, naphthyl(C₁ -C₂)alkyl or anthracenylmethyl.
 3. A compound of the formula: ##STR70## wherein X is chlorine or bromine and R is butyl.
 4. A fungicidal composition which comprises as an active ingredient a fungicidally effective amount of the compound according to claim 1 and an inert carrier or diluent. 